$\left(-x - 8\right)\left(7x + 1\right) = \ ?$
Explanation: $= -x \cdot \left(7x + 1\right) - 8 \cdot \left(7x + 1\right)$ $= \left( -x \cdot 7x \right) + \left( -x \cdot 1 \right) + \left( -8 \cdot 7x \right) + \left( -8 \cdot 1 \right)$ $= -7x^2 + \left( -x \cdot 1 \right) + \left( -8 \cdot 7x \right) + \left( -8 \cdot 1 \right)$ $= -7x^2 + \left( -x - 56x \right) + \left( -8 \cdot 1 \right)$ $= -7x^2 - 57x + \left( -8 \cdot 1 \right)$ $= -7x^2 - 57x - 8$